JPH04117332A - Method of manufacturing aromatic hydrocarbon - Google Patents

Abstract

PURPOSE: To obtain an aromatic compound with high selectivity, by bringing a non-aromatic compound into contact with a catalyst comprising a layered silicate and pillars of an oxide separating the layers of the silicate and comprising specific element(s) while maintaining the catalytic activity for a long time.

CONSTITUTION: A feed containing non-aromatic 2-12C hydrocarbons is brought into contact with a catalyst at a pressure of 100-7,000 kPa, preferably 100-1,500 pKa, a weight hourly space velocity of about 0.05-300, preferably 0.2-10 and a temperature of 200-675°C, preferably 315-595°C, wherein the catalyst comprises a layered silicate, preferably a high silica alkali silicates such as magadiite or kenyaite and pillars of an oxide separating the layers (preferably a distance greater than about 10 Å, especially 15-20 Å) of the silicate and contains at least one element selected from elements of Groups VIA and VIII of the Periodic Table, preferably, gallium and zinc.

COPYRIGHT: (C)1992,JPO

Description

[Detailed description of the invention]

[0001]

[Industrial application field]

Claims 1 to 3, wherein the layered silicate is kenyaite; Claims 1 to 3, wherein the at least one element is chromium.
The present invention according to any one of claims 1 to 5, wherein at least one element in any one of claims 1 to 5 is gallium.
2 Concerning the aromatization of hydrocarbons. [0002]

[Conventional technology]

The production of aromatic hydrocarbons from non-aromatic hydrocarbons using shape-selective catalysts is well known. U.S. Patent Nos. 3 and 7
No. 56,942 teaches such a method using zinc-exchanged ZSM-5. U.S. Patent No. 4,180,68
No. 9 teaches the conversion of 03-C2-C12 hydrocarbons to aromatics using gallium activated zeolites such as ZSM-5ZSM-11, ZSM-12 or ZSM-35. Incorporation of mildly dehydrogenating metals such as zinc or gallium activates the catalyst for the aromatization reaction, but under the high temperature reducing conditions encountered in aromatization, the metal is typically removed, e.g. by elution. There will be a loss. US Pat. No. 4,490,569 teaches a method of reducing such elution by incorporating gallium and zinc into a zeolite aromatization catalyst. [0003]

[Disclosure of the invention]

According to the present invention, a raw material containing non-aromatic 02-C12 hydrocarbons is
A method for producing aromatic hydrocarbons comprising contacting with a catalyst at a pressure of 0 pSi, a weight hourly space velocity of 0.05 to 300(7) and a temperature of 200 to 675°C,
The catalyst comprises a layered silicate and oxide columns separating layers of the silicate and is suitable for groups VIA and VI of the periodic table.
A method is provided comprising at least one element selected from the group consisting of Group IIA elements, gallium and zinc. [0004] Many layered materials are known that have three-dimensional structures that exhibit their strongest chemical bonds only in two-dimensional directions. In such materials, the strong chemical bonds are formed in two-dimensional planes, and three-dimensional solids are formed by superposing such planes on top of each other. However, interactions between planes are weaker than the chemical bonds that hold the individual planes together. The weak bonds are usually caused by interlayer attractions such as van der Waals forces, electrostatic interactions, and hydrogen bonds. If the layered structure has electrically neutral sheets interacting only by van der Waals forces, a high degree of lubricity occurs when the planes slide over each other without encountering energy barriers caused by strong interlayer bonding. is shown. Graphite is an example of such a material. The silicate layers of many clay materials are held together by electrostatic attraction through the ions present between the layers. Additionally, hydrogen bonding may occur directly between complementary sites in adjacent layers, or interlayer bridging may be molecularly mediated. [0005] Layered materials, such as clays, can be modified to increase their surface area. The interlayer spacing can be substantially increased by the absorption of various swelling agents, such as water, ethylene glycol, amines and ketones, which penetrate into the interlayer space and spread out the layers. However, the interlayer spaces of such layered materials tend to collapse when the molecules occupying the spaces are removed, for example by exposing the clay to high temperatures. Such layered materials with increased surface area are therefore unsuitable for use in chemical processes involving any harsh conditions. [0006] The degree of interlayer separation can be estimated by using standard techniques such as X-ray diffraction to determine the fundamental spacing, also known as the "repeat spacing" or "d-spacing." This value indicates, for example, the distance between the top edge of one layer and the top edge of its adjacent layer. If the layer thickness is known, the interlayer spacing can be determined by subtracting the layer thickness from the base spacing. [0007] The aromatization catalyst used in the present invention comprises a layered silicate and an oxide column separating the silicate layers. The oxide pillars are preferably aluminum, boron, chromium, gallium, indium, molybdenum, niobium, nickel,
Contains at least one element selected from the group consisting of titanium, silica, tungsten and zinc,
Most preferably it consists of silica. The oxide pillars preferably consist of polymeric oxides, such as polymeric silica or silica-alumina. It is believed that the degree of polymerization of the oxide pillars influences the final interlayer separation of the layered product. That is, when the degree of polymerization is large, the interlayer spacing of the column-forming layered silicate becomes large. The interlayer spacing of the silicate can be such that the polycyclic hydrocarbon can pass between adjacent layers of the silicate, and the preferred interlayer spacing is IOA or more, or 15A or more, typically 15-20A. [0008] It is desirable to use columnar silicates incorporating 5 to 50 weight percent silica-alumina as the active material in the aromatization catalysts of the present invention. Particularly preferred are silicates containing about 10-20% by weight of silica-alumina as active material. [0009] Suitable layered silicates for the preparation of the catalysts used in the process of the present invention include high silica alkalis such as magadiite natrosilite, kenyaite, macatite, nekoite, kanemite, okenite, debayerite, McDonaldite and ropesite. Contains silicates. These layered silicates have a skeleton consisting essentially of only tetrahedral sheets. That is, silicon is coordinated with four oxygen atoms that are fused together. These materials do not contain octahedral sheets as found in clays where elements such as aluminum are coordinated with six oxygen atoms. High silica alkali silicates can be prepared hydrothermally from an aqueous reaction mixture containing silica and caustic at relatively mild temperatures and pressures. These layered silicates are
It may contain tetrahedral skeleton atoms other than silicon. Such layered silicates contain tetrahedral elements other than silicon, such as elements selected from the group consisting of boron, aluminum, gallium, indium and thallium, and any element which acts as a catalyst when coordinated to the silicate structure. It can be prepared by co-crystallization in the presence of elements. Furthermore, the framework elements other than silicon already present in the layered silicate may be replaced by tetrahedral elements. [00101 For example, synthetic magadiite is readily synthesized hydrothermally from a reaction mixture having the following molar ratio composition: [0011] 5i02/X2O3=10 to infinity. X may be boron, aluminum, gallium, indium and/or thallium or other metals that act as catalysts. = O ~ 0.6, (preferably 0.1 ~ 0.6), M is alkali metal = 8 ~ 500 H20/5102 M OH/ SiO2 R/5iO2 = O ~ 0.4 [R is organic inducer , for example benzyltriethylammonium chloride, benzyltrimethylammonium chloride, dibenzyldimethylammonium chloride, N,N'-dimethylpiperazine and triethylamine. ]. The reaction mixture is heated to a temperature of about 1 to 200 °C to form a product with the following composition:
Retained for any number of days within 150 days. Nitrogen (%) = 0-3, for example 0-0.
3Si○/XO=10 to infinity, X is tetrahedrally or octahedrally coordinated. M20/SiO3=O~0.5, e.g. 0.05~0
．． 1 [0012] Naturally occurring sodium salt N a2S 122045 H2O
Kenyaite, a layered silica acid known to exist as
12204510H20. Synthetic Kenyaite is easily hydrothermally synthesized from a reaction mixture containing the inexpensive starting materials of silica and caustic, preferably KOH. [0013] Layered materials suitable for use in the aromatization process of the present invention can be prepared by the methods disclosed in US Pat. No. 4,859,648. In this method, the phyllosilicate starting material contains ion exchange sites with incorporated internal cleavable cations. Such internally cleavable cations may include hydrogen ions, hydronium ions or alkali metal cations. The starting material is treated with a "pillar-forming" agent comprising a source of organic cations to spread out the layer of the starting material by exchange or addition of internally cleavable cations. In particular, alkylammonium cations have been found to be useful. That is, C3
and higher molecular weight alkyl ammonium cations,
For example, n-octylammonium can be easily incorporated into the interlayer species of layered silicates, thereby stretching the layers to allow for the incorporation of polymeric oxide precursors. The degree of interlayer spreading can be controlled by the size of the organic ammonium ion used, and with n-propylammonium cations a d-spacing of about 2-5 A or a spread of about 2-3 A can be achieved. , 10~
To obtain a d-spacing of 20 A, an n-octylammonium cation or a cation of comparable chain length is required. The organic ammonium cation that separates the silicate layer is
It can also be formed in situ by reacting neutral amine species with interlayer hydrogen or hydronium cations of the layered silicate starting material. [0014] The polymeric oxide pillars are formed from precursors that are preferably introduced between the layers of organic "pillar-forming" species as cationic or more preferably electrically neutral hydrolyzable compounds of the desired elements. Ru. The precursor material is preferably an organic compound containing the desired elements mentioned above that is liquid under atmospheric conditions. In particular, hydrolyzable compounds, such as alkoxides of the desired elements of the pillars, are used as precursors. Suitable polymeric silica precursors include tetraalkyl silicates, such as tetrapropylorthosilicate, tetramethylorthosilicate and most preferably tetraethylorthosilicate. The introduction of an element selected from the group consisting of aluminium, boron, chromium, gallium, indium, molybdenum, niobium, nickel, titanium, thallium, tungsten and zinc into a columnar system of internally cleavable polymeric oxides transforms the layered chalcogenide into silicon. This can be achieved by contacting the hydrolyzable compound of the desired element with the organic pillar-forming species before, after or simultaneously with contacting the compound. The hydrolyzable aluminum compound used may be an aluminum alkoxide, e.g. [0015] Subjecting the polymeric oxide precursor-containing product to suitable conversion conditions, such as hydrolysis and/or calcination, to form the layered material used in the present invention. The hydrolysis step can be carried out by any method. Because of the effect of internally cleavable water on hydrolysis, the extent of hydrolysis is determined by drying the organic "pillar-forming" species before addition of the polymeric oxide precursor. It can be corrected by changing the degree. The product after conversion to the polymer oxide form can be subjected to conditions that remove organic compounds such as organic cationic pillar formers, e.g. to high temperatures such as those encountered in calcination in air or nitrogen. . [0016] After forming polymeric oxide pillars by hydrolysis and calcination to remove the organic pillar-forming agent, the final pillar-forming product may contain exchangeable residual cations. Such residual cations in the layered material can be ion-exchanged with other cationic species by known methods to impart or alter the catalytic activity of the pillared product. In particular, gallium or zinc components or the periodic table [Fisher Scientific Company (Fisher 5 scientific company)
Published by Fic Company, Catalog No. 5-70
2-10.1978] Groups VIA and VIII
Components containing Group A elements can be introduced by ion exchange or impregnation techniques known to those skilled in the art. Representative ion exchange techniques are disclosed in U.S. Pat. Nos. 3,140,249, 3,140,251 and 3,140,2
It is disclosed in many patent documents including No. 53. usually,
The aromatization catalyst of the present invention comprises about 0.1 to 20% by weight, preferably about 0.5 to 15% by weight of gallium, zinc, VI
Group A or Group VIIIA metals may be included. [0017] Pillar-forming silicates include silica-alumina, silica-magnesia, silica-zirconia, silica-thoria, silica-beryria and silica-titania, ternary compositions such as silica-alumina-thoria, silica-alumina-zirconia , silica-alumina-magnesia, and silica-magnesia-zirconia. The matrix may be cogel-like. The relative proportions of the pillar-forming silicate component and the inorganic matrix can vary widely, ranging from 1 to 99% by weight silicate content of the dry composite, more typically from 5 to 80% by weight, on an anhydride basis. [0018] The aromatization reaction of the present invention involves contacting a suitable feedstock with a catalyst of the present invention under sufficient aromatization conditions. Such conditions are 100 to 7000 kPa (atmospheric pressure to 10100 kPa
A pressure of 0 psi, preferably 100 to 1500 kPa (atmospheric pressure to 200 psig), a weight hourly space velocity of about 0.05 to 300, preferably about 0.2 to 10, and a weight hourly space velocity of about 20
Temperatures of 0-675°C, preferably about 315-595°C may be included. [0019] The feedstock may include one or more C-C non-aromatic hydrocarbons, sometimes C6-C2-C12 paraffins, most preferably n-paraffins. [0020]

【Example】

As a practical group, 80 g of silica kenite directly swollen with cetyldimethylethylammonium bromide and impregnated with tetraethyl orthosilicate (TE01) was mixed with 0.5 M Ga (NO3).
) Silica/gallium columnar Kenyaite was prepared by suspending it in 3200 g. The slurry was stirred for 2 hours, filtered, air dried, and calcined at 540° C. for 3 hours. [0021] The material obtained had the following properties: surface area, m2
/g 593 minutes, 1000℃
, weight% 93.3Si○2, weight%
87.2Ga, weight%
4.2A1203, ppm720 [0022] Implementing group A In the same manner as in Example 1, 200 g of silicate was
Silica/alumina pillar-forming silica kenite was prepared by suspending it in 31000 g of (NO3). 1 slurry
Stirred for 8 hours, filtered, air dried, and calcined in air at 540° C. for 6 hours. [0023] The obtained material had the following properties. Surface area, m2/g 582 ash content,
1000℃, weight% 90.58Si○2,
Weight% 85.3A1203, weight% 2.9, ppm
305[0024] ZSM-
5 samples were prepared. Take this sample carefully.
Calcined by heating to 538°C at a heating rate of 0.5°C/min in a nitrogen stream (10v/v/min) and held at that final temperature for 2 hours in nitrogen, after which the atmosphere was changed to a dry air stream. (10
v/v/min). After cooling the ZSM-5 catalyst to room temperature, 5 CC/g of 1. Ion exchange was performed twice at room temperature using ON NH4N○3 solution. During ion exchange,
The catalyst was thoroughly rinsed with deionized water. 1 ZSM-5 catalyst
After drying overnight at 20°C, the catalyst was heated with a dry air stream (10v
/v/min) at a rate of 0°1°C/min to 538°C and maintained at that temperature for 3 hours in a stream of air. [0025] The finally obtained catalyst had the following properties. SiC2, weight% 94.2A
1203, weight% -2.3 Na, ppm 350
Ash content, 1000℃, weight% 96.5[0
[026] The three catalysts from Example 1.2.3 were pelletized,
Grind and cut into 40/80 mesh size, inner diameter 0.64
cm tubular quartz reactor. The catalyst was preheated to 538° C. in a helium stream (200 cc, 7 minutes) at a heating rate of 30° C./min. The catalyst is at the reaction temperature (538℃)
After the helium flow to each reactor was reached, the helium flow to each reactor was adjusted to 98.9% n-hexane (98.9% percolated in A1203).
Switched to a liquid sparger device filled with (hexane). The helium-hexane mixture was cooled to 15.9° C. using a circulating glycol cooling condenser to maintain the hexane partial pressure at 100 torr (13,3 kPa). [0027] The helium flow rate was adjusted to obtain an n-hexane conversion of 5-25% by weight. After 1 hour, six analyzes were performed on each catalyst to determine activity and relative aging rates. The analysis results of these three types of catalysts are shown in Tables 1.2 and 3. The benzene selectivity is given by the following formula: [0028] k is the reaction rate constant 7 s-1 assuming that the conversion of n-hexane is a first-order reaction [0029]

[Table 1] [0030] Gope saw to de U two Toad U) + ＼τ C) C C C S to ;) one) Otsu Otsu \; X; state

[Table 2] O

[Table 3] C Kusi N C) a Fluoro From a comparison of these results, it can be seen that the benzene selectivity is highest when columnar gallosilicate is used. It is noted that after approximately one hour of flow, the benzene selectivity of this material has further improved. That is, the maximum benzene selectivity for the pillared gallosilicate is 0.5-2 to 20% excess of the pillared gallium-free layered silicate of Example 2 and about 0.5% excess of the ZSM-5 catalyst. Te, 4
1% excess [0033] Tables 1 and 2 also show that gallosilicates are more active than similar non-gallium-containing materials and are at least as stable. After 1 hour of flow, the rate constant of the gallosilicate is approximately 15% less active than the pillar-forming gallium-free phyllosilicate (k from 1.30 x lO-4 s-1 to 1.11 x'l O-4 s). -1), whereas 8
% reduction (from 2,07 x 10-4 s-1 to 1.94
X10-4 seconds-1). The high degree of stability of the two pillar-forming layered gallosilicates is unexpected in view of their high aromatic selectivity. Normally, under comparable reaction conditions, aromatic compounds, especially alkyl aromatic compounds, tend to condense and form coke on the catalyst surface, so a high aromatic selectivity increases the rate of catalyst aging [bar C, HlB artholom
ew), [catalyst deactivation (Ca
Chemical Engineering
earing), Volume 91, November 12, 1984,
page 96]. This coke limits the pores of the catalyst and covers the active sites, thereby degrading conversion activity. [0034] The product distributions from the conversion of n-hexane using column-forming layered gallosilicates and gallium-free silicates for N runs are shown in Tables 4 and 5, respectively. These data show that gallosilicates - throughout - produce highly desirable toluene at high levels and less desirable Class C low levels. Light gas (C1+C2, C3
- and C4-) all decreased, and toluene and benzene selectivities increased with flow time. This result is also unexpected since ZSM-5 based catalysts for this type of reaction show a consistent loss of activity with flow time. [0035]

[Table 41 -Heto(:'-5CM - 1←■ToO 0■Todo■ 0ToheOSosun0 OO00ToLr100 C1") -C'J Shi000 C',)
C) 11100000') 0■000-One inch! − ≦“ ト■ ＼; -hezunchoba) no■so-ctsu-cX:i maba) [F]to!-10-ICto■ 0-, -t 0 m e:'J u ') 0 CD C'(', 1 Ma000 0 (X) size -C prisoner Φ-■'s'') to cc■O 1 size←to--% 0 0ri0QΩ-(1m) 0 - Lf') L'-) 0'M -〇'l"l <, = [Table 5] Kenyaite impregnated with Tetraethylorthosilicate (10g
, 60%) was passed through Cr(N), air-dried, and
It was baked at ℃ for 6 hours. The composition and surface area are shown in Table 6. [0038] Implementation group L Silica column forming (Si) Kenyaite (2g) with Cr(NO
3) Impregnation with an aqueous solution of 3 (0.223 g in 2 g of water). This material was calcined in air at 540°C for 3 hours. The composition and surface area are shown in Table 6. [0039] Example 1: Silica column formation (Si) Kenyaite (5 g) was added with Cr (NO
3) An aqueous solution of 3 (1.2 g in 5 g of water) was impregnated. This material was rolled for 1 hour and then heated to 540°C in air.
It was baked for 3 hours. The composition and surface area are shown in Table 6. [0040] Implementation report amorphous silica gel [Ultrasi
1), 5 g] was impregnated with an aqueous Cr(NO3)3 solution (1.2 g in 7 g of water). This material was rolled for 2 hours and then calcined at 540°C for 3 hours. The composition and surface area are shown in Table 6. [0041] Amorphous silica gel [High-Sil]
), 5g] was treated in the same manner as in Example 9. The composition and surface area are shown in Table 6. [0042] Cr from Kaiser Flumina (15g)
(NO3)3 aqueous solution (3.6 g in 15 g of water) was impregnated. This material was rolled for 1 hour, then 540
It was baked at ℃ for 3 hours. The composition and surface area are shown in Table 6. [0043] A sample similar to Main Example 11 was prepared. Before treatment, only the alumina was fired at 540°C for 3 hours. The composition and surface area are shown in Table 6. [0044] Starting from the implementation stage, the catalyst samples prepared in the above examples were tested for 06 and C7 alkane dehydrogenation. A fixed weight of catalyst was charged into a small Pyrex reactor. n-hexane, or n-
Other specific feeds such as hebutane or cyclohexane were introduced into the catalyst bed at 2WH3V. Operating conditions were temperatures of 480-540°C (900-1000°F) at atmospheric pressure. After a specified period of flow, a sample of the product was analyzed by on-line gas chromatography using a fused silica capillary column. The results are shown in Tables 7 and 8. From the table, the catalyst of the present invention shows improved conversion and selectivity compared to using amorphous silica catalyst,
It can be seen that there are fewer undesirable non-selective side reactions such as cracking than when using an alumina catalyst [
[0045] Propane was dehydrogenated using the catalyst of Example 6. are summarized in Table 9. [0046] Process conditions and results thereof

[Table 61 ■ and bush C \de Hagi Ma a○ O') C) oO Very Howl Next [Table 7] 0ri ,\ \; of C co X is Xna to

[Table 8]

[Table 9] Propane dehydrogenation test conditions Temperature "F ('C)" Propane WHSV 2 2TO
8 (minutes) 1 o t. Conversion rate i 8,7 3
8.4C3 olefin selectivity 74,262.1
Product distribution C” 4,7 14.
OC313,923,8

Claims (7)

[Claims] Claim 1: A raw material containing non-aromatic C2 to C12 hydrocarbons is heated at 100 to 7000 kPa (atmospheric pressure to 1000 psi).
g) contacting a catalyst at a pressure of 0.05 to 300, a weight hourly space velocity of 0.05 to 300 and a temperature of 200 to 675°C, the process comprising: contacting a catalyst with a layered silicate and comprising oxide columns separating layers of silicate, and comprising at least one element selected from the group consisting of elements of groups VIA and VIIIA of the periodic table, gallium and zinc. How to characterize it. Claim 2: The pressure is 100 to 1500 kPa (atmospheric pressure to
200 psig), a weight hourly space velocity of 0.2 to 20 and a temperature of 315 to 595C. 3. A method according to claim 1 or 2, wherein the pillars are composed of polymeric silica. 4. The method according to claim 1, wherein the layered silicate is magadiite. 5. The method according to claim 1, wherein the layered silicate is kenyaite. 6. The method according to claim 1, wherein the at least one element is gallium. 7. The method according to claim 1, wherein at least one element is chromium.